Many Roman Emperors were murdered shortly into their reign. Probably the most famous sequence of this occurring in Roman history is the "Year of the Four Emperors," that being the year 69 AD. The name is quite literal.

Following the death of Nero by suicide in June of 68 (after he was declared a public enemy by the Senate), Galba, who had been governor of Hispania Tarraconensis, became Emperor (by basically managing to reach Rome with an army before anyone else could do that).

Galba reigned for seven months before he was killed in January 69 by Praetorian Guard members in a conspiracy led by Otho, who had once been a supporter of Galba.

Otho survived for around 3 more months, before he committed suicide in April after losing a battle to Vitellius (who was supported by legions in Germany that had opposed Galba and Otho).

However, a rival emperor, Vespasian, was crowned in Caesarea (in Judea) with the support of the governor of Syria and legions from across the Roman East and the Balkans. Most of Vitellius's supporters deserted him, and in December Vespasian entered Rome, had Vitellius killed, and became the sole Emperor. Vespasian would hold onto that position until he died of illness ten years later.

The shogun Oda Nobunaga was betrayed and killed by his general Akechi Mitsuhide, who was then himself killed by the forces of Toyotomi Hideyoshi in battle less than two weeks later. Hideyoshi went on to die of old age.

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